OAS 4.0 Trapping missing URLs

I am a bit stumped with this one and so wondered if anyone has done this before and can help.

I have a Oracle Application Server with about 1.5 million TIF image files on. These files are arranged in a three-tier directory structure under a couple of virtual directories.

I have an application running on the same machine that provides HTML screens to allow searches to be done on indexes of these files. The search results are in the form of a list of URL links pointing directly at these TIF files (on their virtual directories). By clicking on one of the TIF URLs then the image can be viewed - the browser launches the defaut TIF image viewer automatically.

Now the problem: a number of these TIF files are missing and the user gets 'URL not found' rather than the image file (via the standard WinNT image viewer). Is there a simple way that I can catch this error in the application server and present a more friendly message to the user? I don't want to catch other errors - just a missing URL under a given virtual directory.

I have thought of providing a CGI script as a level of indirection since the script would run on the same machine and could check that the file existed before presenting it for download - but I am looking for a simpler (quicker more cost-effective) solution. I have also looked at converting the images to GIFs on the fly, but again this is more complex as I would need to provide functionality to allow resizing and rotating - things the standard image viewer does for free.

I would appreciate any help.

Regards,

Jason Judge Received on Mon Jun 21 1999 - 17:47:49 CDT